Have you also added the map data to the server, because when you click on the minimap the client doesnt check if you the walk is possible or not. The server will do the calculation then if I remember it straight.
So if you haven't added the map data to the server do it, and try again.
EDIT : Make sure you got a region system at all too.. wich is checking the walking on the server side also, so you cannot cheat around that way.